In a navigation system boarded on a vehicle, an art is known that the amount of traveling energy necessary for the vehicle to reach a destination is calculated on the basis of information about a road on a traveling route set for the vehicle in advance (see Japanese Patent Application Publication No. 2010-210271 A).
However, in the art disclosed in Japanese Application Publication No. 2010-210271, what is calculated is only the amount of traveling energy necessary for the vehicle to reach the destination. For that reason, according to the art described in Japanese Application Publication No. 2010-210271, a problem arises in that a user cannot know a predicted remaining amount of traveling energy while a user drives the vehicle.